Photographic backing paper



R iuued Na. 21, 1939 UNITED STATES a Re. 21,268

PATIENT ormcs.

' to Eastman Kodak Company, Rochester a corporation oi! New Jersey NoDrawing. Original No. 2,153,130, dated April 4, 1939, Serial No.101,015, mm 2, 1931.

Application for reissue September 30, 1939,

Serial No. 297,361

3 Claims. (01. 95-5) This invention relates to an improved photographicbacking paper and to a photographic cartridge including such backingpaper.

The principal object ofthe invention is to pro- 5 vide such a backingpaper and cartridge in which the ink used to form the indicia thereonhas certain properties of particular utility and advantages of thisparticular purpose.,

Such indicia are preferably printed by the i0 rotogravure process and anink suitable for use in that process is, therefore, desirable.

A perfect rotogravure ink should be of low viscosity and have lowsurface tension; it should .20 Most rotogravu-re inks have been "spiritinks;

that is, inks made with highly volatile organic solvents. These solventsare highly flammable Inks in which and many of them are toxic.

water is used as the solvent have had high surlace tension, and havegiven proofs of the poorest quality.

" Inks for printing photographic backing paper,

such as for printing the white or black numerals,

etc., on the green or red backing paper which protects photo raphic rollfilm, have been of two types: water inns and spirit inks. Water inks arecomposed of a water-soluble dye (or a pigment),

a water-soluble binder, such as gelatin, agaragar, or casein, and water.Spirit inks are composed of a spirit-soluble dye (or a pigment), a

spirit-soluble binder, such as a resin, and an organic solvent; I

Patent 807,458; it is desirable that the backing paper be printed withink having the'same hygroscopic qualities as the surface'oi the paper;otherwise, under some conditions of storage, particularly under tropicalconditions, the nume'rals reproduce themselves photographically on thesensitized emulsion of the fllm. The paper is usually coated or sized,after printing, with an aqueous solution of gelatin, agar-agar, casein,'etc. when the printing resulting from a watersoluble ink is coatedwith'such an aqueous solution, smearing of the printing often takes place.

In the same way, the printing resulting from spirit-soluble inks smearsif the paper is overcoated with a spirit-soluble coating. A water inkcannot be used with a spirit-soluble overcoating, or a spirit ink "witha water-soluble overcoating, because of the resultant difference inhygroscopicity. It has not hitherto been possible to use the rotcgravureprocess for printing the numerals, etc., on photographic backing pa-'per. The resins used in rotogravure inks are so moisture-resistant, andmany oi them are photo- As' has been shown in U. S.

graphically active, causing fogging of the photographic emulsion on thefilm with which the paper is used. Water inks, such as those describedin U.. S. Patent 807,458, will not print by the rotogravure process. I 5I have discovered that zeinand the'other prolamines, such as gliadin andhordin, which are soluble in. aqueous alcohol, are excellent binders forrotogravure inks, and that such inks are very satisfactory for printingphotographic 10 backing papers. The prolamines are insoluble in wateralone and in organic solvents alone; hence printing resulting from anink in which a prolamine is the binder does not smear when coated witheither an aqueous solution or a spirit solu- 15 tion. The prolamines arewater-susceptible, however, being swelled by moisture in a mannersimilar, to gelatin or casein. ,Thereiore,

' photographic paper can be printed 'with an ink in which the binder iszein or another prolamine, 20 and then coated with an aqueous solutionoi! gelatin or casein, etc. The printing will not smear, and will havethe same hygroscopic qualities' as the overcoating. Moreover, theprolaniines are 'not photographically active, so that they do not fog ordesensitize the emulsion on photographicfilm -with which the paper maybe rolled up.

My novel inks containing a prolamine as a binder iulflll'therequirements 01' a perfect rotoo gravure .ink as well as do ordinaryrotogravure inks, and in addition the flammability and toxicity oi. thesolvent are much less than those oi! v the solvents ordinarily used inrotogravure inks.

In addition, the use of water as part 01 the sol- 35 vent reduces thecost of the ink.

Among the alcohols and other organic solventswhich may be used withwater to dissolve zein or other prolamines are:

water.

A suitable rotogravureink containing min or other prolamine as abindermay'liave the'iol- 5i lowing general iormulaz Organic solvent(s)parts;.. -50.to Water o 50to10 Y Dye. parts or more 2to, 5

The dye may be 'any'dye that is soluble in the solvent-water mixture andis not photographically active. such, for instance. as:

' place of a dye,' a' pigment, such, for instance. as titanium oxide orcarbon black may be used in suitable amount. In inks for printingphotographic" backing paper, I prefer to use 5 Spirit Nigrosin N. B. forblack ink, and titanium 'oxidei'orwhiteink. v f

I-give below, by .way 01 examples, a number of formulae for inks which Ihave found satisand by selecting a solvent of the proper boiling ExampleI Ethyl alcohol a. --c '15 Monomethyl ether of ethylene glycolcc- 75Zein grams 20 Water cc 50 Nlgrosin'N. B grams 10, .30 V Example}! vMonomethyl etherot ethylene glycol ..-cc 160 zein grams 20 Water ccTitaniumpxide grams 80 scam'mm.

Ethyl 'alcoholcc 300 n-Butyl alcohol cc '.-100.

Zein' grams 60 Nigrosin N. B... -c grams l8 Example Ethyl alcohol cc 320Zein grams 8 Water--- v Y 80 Nlgrosin N. B grams. 8

I ,E'mmple V Ethyl aieoho1 l '-.cc 150 Monomethyl etheroi' ethyleneglycol cc 150 Zein: 'grams 40' water. cc, Nigrosin N B--- grams 0Example VI r Ethyl alcohol 'cc Monomethyl ether oi ethylene glycol .cc180 Zein 20 W (l0 Nis'rosin H. B"; "ms" 10 "States is:

:matter, and overcoated with a colloid,-su 7 per having the .propertythat, when the indicia sitized layer carrying indicia composed of a nonv lzarnple vll Monomethyl ether oi ethylene glycol cc 4N i Water V c 1MTitanium o'xide "gramm m Example vm Et alnnhnl no 49o Zein. 3 grams 5G10 Water 100 Titanium oxide grams 300 What! claim as myiinvention anddesireto' be secured by Letters Patent of the United 1..Photographicpaper carrying indiq cia composed ot-a non-hardened prolamine andfactory The printing and drying characteristics coloring matter,overcoated with a colloid.

so may be controlled by the concentration of zein 2. Photographicbacking papercarrying indicia composed oi'non-hardenedrei-n'and coloringmatter, over-coated with a colloid.

3. An un'sensitized, opaque, photographic back ing paper carrying on onesurface indicia composed oi 'a non-hardened prolamine andcoloringbearing surface is maintained in contact with a will'not 'aflectthe emulsion. I g

4. A roll film cartridge comprising inter-rolled strips of film having asensitized layer and of unsensitized backing paper, that surface. of thebacking paper which is in contact with the senphotographically sensitiveemulsion, the in'dicia hardened prolamine and coloring matter an beingovercoated with:a colloid.-

5. Photographic backing paper carrying indicia composed-of anon-hardened prolamine and coloring matter, overcoated with awater-soluble colloid.

6.Photographic backing paper carrying i'ndi- I -cia composed ofnon-hardened zein and .coloring matter, overcoated with a water-solublecol- 74 An unsensitized, opaque; photographic 45 backing paper carryingon one surface indicia composed of a non-hardened prolamine and colorlngmatter, and overcoated with a water-soluble colloid, such paper havingthe'proper y that. Y

when the indicia-bearing sui'ace is maintained in :50 contact with aphotogaphicall'y sensitive emul-. sion, the indicia will not aflect theemulsion.

8. A roll iilm cartridge-comprising inter-rolled strips of fllm having asensitized layer" and of unsensitized backing paper. that surface of the55 backing paper which is in contact with the sen-- 'sitized layercarrying indicia of anon; [hardened prolamine and coloring matter andbeinl overcoated with a water-soluble colloid.

